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Poll: Do you use a subwoofer? (Explain why/why not)

Do you use a subwoofer? (Explain why)

  • Yes

  • No


Results are only viewable after voting.

GrimSurfer

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If spec "60-22k Hz +/- 3 dB" is correct I would stick to 80Hz XO point (or even 60Hz) to help energize the room with mains as well in addition to 2 subs. As long as your mains can play 60Hz with decent SPL and THD that makes IMO. LF Linearity should anyhow be dealt with DSP.

I had initially calculated the xo at 90 Hz (see graph) but still had a frequency dip (not a notch) when the sub was set there.

So then I ran REW for the mains only. Then separately for the sub (I started out with one sub). The sub rolled off a little steeper than advertised (don't recall the exact figure, as these are in the notes that are "carefully archived" (LOL) in the crap hole I call an office).

Using the figures, I then recalculated the xo. That came out higher than I thought it would, still not high enough as the pot on the sub was off by about 10 Hz. Fine tuning was done with level after that.

I guess part of the issue is my bookshelf speakers. They handle the mids and highs nicely but aren't so great down low. Many days spent positioning them relative to the back wall for bass reinforcement but one can only expect so much from a ~14x9x8 bookshelf containing a 6" main driver.

That's what got me onto asking @LarsF about his bookshelf speakers. A useable 34 Hz is much lower than I would expect from a passive bookshelf. I could see 40-ish with a rear firing port and corner reinforcement. But traces don't lie, so I can't question his decision to hold off on getting a sub (particularly if his space is average/small, his listening levels modest and the power handling of his bookshelves high).
 

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GrimSurfer

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jonmichael

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A pair of SVS sealed (2000s) makes my bookshelf speakers sound better than any towers I have owned at half the space and WAF.
 

Krunok

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I had initially calculated the xo at 90 Hz (see graph) but still had a frequency dip (not a notch) when the sub was set there.

So then I ran REW for the mains only. Then separately for the sub (I started out with one sub). The sub rolled off a little steeper than advertised (don't recall the exact figure, as these are in the notes that are "carefully archived" (LOL) in the crap hole I call an office).

Using the figures, I then recalculated the xo. That came out higher than I thought it would, still not high enough as the pot on the sub was off by about 10 Hz. Fine tuning was done with level after that.

I guess part of the issue is my bookshelf speakers. They handle the mids and highs nicely but aren't so great down low. Many days spent positioning them relative to the back wall for bass reinforcement but one can only expect so much from a ~14x9x8 bookshelf containing a 6" main driver.

That's what got me onto asking @LarsF about his bookshelf speakers. A useable 34 Hz is much lower than I would expect from a passive bookshelf. I could see 40-ish with a rear firing port and corner reinforcement. But traces don't lie, so I can't question his decision to hold off on getting a sub (particularly if his space is average/small, his listening levels modest and the power handling of his bookshelves high).

I always thought that XO point is determined from the ability of the drivers to produce SPL with a reasonable distortion (confirmed by measurements), not on calculations. I would defintiely want to know on what model were your calculations based. According to specs, and I'm sure measurements would have confirmed it, your speakers should be good down to 60Hz, so what was your exact logic to push XO point that much upper?

I can't relate the measurement you posted with the 60-22kHz +/-3dB specs claim.
 
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GrimSurfer

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The calculations were based on SPL at the listening position.

If, for example, the bookshelves were 6 dB down at frequency "x", then adjusting the sub x-over to come in at +6dB at that same frequency would smooth the overall SPL at the listening position. The trick, I suppose, is to account for natural and filtered roll-off, differences in distance, room response, etc.

I've found that calculations based on manufacturer's anechoic data (as I've since learned is something that Floyd Toole advocates) can get a person a wee bit closer than simply starting with an arbitrary x-over point like the THX 80 Hz setting. I started down that arbitrary track initially until I started noticing the same drop out. After ripping out my hair (why isn't 80 Hz working for me?) I started asking myself "why 80 Hz?" and "how did my sub manufacturer arrive at this figure without knowing the response of my mains?"

Active crossovers on the mains and sub would massively simplify things (perhaps to the point where you could choose an arbitrary frequency) but you'd still need measurement to adjust for room gain.

At least that's my thinking, FWIW.
 
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LarsF

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Rear firing port?
No, a port at front, look at spec's here https://guruaudio.com/?page_id=212
They should be placed as close to the wall as possible with some damping material between speakers and wall. I'm very pleased with them, I think they sound very good. Starting to play with BruteFIR plugin in Volumio, but I should prefer to do room adjustments, but I think my wife prefers something that's invisible.
 

GrimSurfer

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All wives prefer invisible, my friend!

Cool. Thanks for the link.

I've considered damping material between the cabinet and wall too, as aesthetics and practical issues force me to place my speakers half as close to the wall as B&W recommends. Have you found any interesting products?
 

LarsF

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Ron Party

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For years now, I've been enjoying two Seaton Submersive HP+ subs. Wouldn't be without 'em.
 

josh3010

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I listen to a lot of bass heavy music and do a bit of gaming so with my Micca MB42X's i felt the need for a subwoofer (dayton sub-1000), really helps with dynamics in the lower end of the spectrum and helps fill in the room (9.5ft x 10.5ft) :)
 

GrimSurfer

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mikewxyz

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I haven't tried to add subwoofers (2) to my system although the argument for doing so is compelling. It's not so much the cost as the complexity of integration. Credible people have said they have to constantly adjust the subs to keep them sounding right. However, based on the survey, it looks like a clear majority prefer subs.

For now, I'm giving up the bottom octave for simplicity.
 

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Bald1

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I've got a custom 18" unit mated to my biamped Magneplanar IIIa's in my main stereo system. And a pair of Outlaw (Hsu designed) subs as part of a 7+2 Definitive Technology home theater speaker system. The why's should be obvious. The subs in both systems add the missing lower registers and the visceral punch large volumes of air they move provide. :D:)
 

30 Ounce

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I haven't tried to add subwoofers (2) to my system although the argument for doing so is compelling. It's not so much the cost as the complexity of integration. Credible people have said they have to constantly adjust the subs to keep them sounding right. However, based on the survey, it looks like a clear majority prefer subs.

For now, I'm giving up the bottom octave for simplicity.
A properly setup sub will not need to be readjusted constantly. That is a clear sign of an improperly setup sub. I would not recommend setting up a subwoofer without REW and a calibrated mic or some other means of measuring. Doing it by ear is really difficult and plagued with subjectivism which is why people constantly change their settings.
 
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Deleted member 4987

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A 'no' from me, but very curious and would love some suggestions, the normal 'audiophile' sites just add more confusion for me.

Because:

1. I'm running a rega elex r into Harbeth P3sers, there seems to be no agreement on the best wave of connecting a sub to the amp. Any discussion has turned into an arguement between those favouring using the pre-out and other favouring some other solution which I don't understand.

2. Room placement choices are limited and generally pretty closed in.

3. I live in a Parisian appartment with very tolerant neighbours above and below. I'd like a bit deeper base but without vibrating their pictures off the walls.

4. I love the tonality of my speakers and it seems that I'd need to spend a lot of money on something worthwhile.

Any pointers?
 

JohnBooty

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I'd prefer not to run subwoofers at all. The ideal speaker would, obviously, have a single driver and play all the frequencies. Since that's infeasible, we go for various compromises and those compromises include subwoofers at times.

In my music system I currently run JBL 306P's crossed over to a pair of SVS SB-1000s. Sometimes I switch things up and run my Classix II (DIY) speakers full-range with no sub, since they have lovely output down to the 30hz range on their own.

I have a large pair of speakers with 15" woofers in the garage, and they don't need a sub either. They go down to the 20hz range on their own.

My living room TV system has a typical 5.1 setup with a Hsu sub.
 

Willem

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B&W recommended to set the crossover frequency of my PV1d sub at the -6dB of the main speaker (or at 0.7 times the -3dB frequency of vented speakers and 0.6 times the -3dB frequency of closed systems), with a 4th order slope and 0 degree phase for vented systems and a 2nd order filter and 180 degree phase for a closed system. For me, this worked very well as a first approximation, with my Quad 2805s treated as if they are vented speakers (bass response falls off pretty quickly) and my Harbeth P3ESRs as closed systems.
And as a response to Deirf: I normally use my P3ESRs without a subwoofer, but that is in my study. I did try them with a sub in the large living room and the result was very impressive. So my recommendation would be to use two small subs with the crossover set at about 45 Hz. Two small subs give a rather smoother response (four would be even better but may be too much in what is probably a smallish room). I would also use a Dspeaker Antimode 8033 room eq unit to smoothen the response even further. Since the AM 8033 assumes line level input, the simplest connection would be from the pre amp output, assuming that this is volume controlled. If the line out has a fixed volume output, you will need to connect at speaker level, with an attenuating cable to the AM 8033 (this is how I did it for years).
 
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Midwest Blade

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Have had a Velodyne for many years used with a bookshelfs for a home theater system. Took it out of service in the condo due to noise rules and having moved away from HT. Still have it in storage and do not need it in my main system, probably heading to recycling one day.
 
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Deleted member 4987

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Very useful. Any recommendations for small subs, something used would be ideal. Room is 5.5m x 4.5m.

Is it possible to have subs on shelves?
 
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